Sternum buckle



FIG. 1 is a perspective view of a sternum buckle in accordance with thenew design;

FIG. 2 is a top plan view of the sternum buckle;

FIG. 3 is a bottom plan view of the sternum buckle;

FIG. 4 is a left side elevational view of the sternum buckle, the rightside elevational view being mirror image of the left view;

FIG. 5 is a front end elevational view of the sternum buckle; and,

FIG. 6 is a back end elevational view of the sternum buckle.

The broken lines in the drawings form no part of the claimed design.

The ornamental design for a sternum buckle, as shown and described.